1. Field of the Invention
The present invention relates to a fluoroboron compound which is useful as an aminomethylating agent to directly introduce a primary, secondary, or tertiary aminomethyl group to an aromatic ring, and to an aminomethylating reaction for an aromatic ring using the fluoroboron compound.
2. Description of Related Art
The structure of an aromatic ring containing an aminomethyl group (hereinafter, may be referred to as an “aminomethyl aromatic ring”) is widely used in medical compounds, and has high industrial applicability. For example, the patent document 1, which relates to a novel antifungal agent, discloses a compound containing an aminomethyl aromatic ring in a part of the chemical structure (hereinafter, may be referred to as an “aminomethyl aromatic compound”). Of compounds containing an aminomethyl aromatic ring, a compound containing a primary aminomethyl aromatic ring is frequently used as a precursor for a compound containing a secondary or tertiary aminomethyl aromatic ring, and therefore, many types of the compounds is sold as a reagent in a market.
Conventionally, as a method of obtaining a compound containing the aforementioned chemical structure, a synthetic method, which uses a reduction reaction, and a synthetic method, which uses a compound containing a halomethyl group-containing aromatic ring as a precursor, have been reported.
A reaction, which uses a metal catalyst to directly introduce an aminomethyl group to an aromatic halide substrate such as chlorobenzene, has never been reported as a production method of an aminomethyl aromatic ring.
As an aminomethylating reaction using a metal catalyst, a sulfonylaminomethylating reaction for enol triflate using an organotin compound was reported as disclosed in non-patent document 1.
Also, the non-patent document 2 discloses an aminomethylfluoroboron compound, and the non-patent document 3 discloses an aminomethylboron compound whose structure is similar to that of an aminomethylfluoroboron compound. However, an aminomethylation reaction for an aromatic ring using these compounds has never been reported.    [Patent Document 1] PCT International Publication No. WO2005/033079    [Non-Patent Document 1] Org. Lett., 2000, 2, 1081    [Non-Patent Document 2] Org. Lett., 2006, 8, 2031    [Non-Patent Document 3] J. Org. Chem., 1968, 33, 3055